Intelligence is a general term referring to the overall capacity for learning and problem solving. It is a single pure ability, which varies in amount. David Wechsler defines intelligence is the aggregate or global capacity of the individual to act purposefully, to think rationally, and to deal effectively with his environment. Intelligence tests-Most theorists view intelligence as consisting of many abilities. Each theory about the organization and nature of intelligence of course implies a somewhat different way of sampling people’s behavior to yield estimates of their mental ability.
G factor theory, for example, suggests that a single score will represent intelligence adequately. Theorists proposed different sets of factors. Guilford and his associates have been working diligently to develop at least one, and usually more than one, subtests for each of the 120 cells in his three dimensional model (Morgan, 1981). There are a number of intelligence tests available to the psychologist, and a good psychologist selects the most appropriate test based upon the needs of the student. Generally, the two most popular individually administered intelligence tests are the Stanford-Binet Intelligence Scale and the Wechsler Scales.
Wechsler Intelligence Scale for Children, 3rd. ed. (WISC-III) 1991: The Wechsler Intelligence Scales for Children-III (WISC-III) is used for students ages 6 through 16. It measures verbal and nonverbal performance skills (five parts for each). The test is made up of 11 subtests that are part of the IQ measure. One half of these tests require verbal logic and reasoning. The remaining subtests looks at nonverbal reasoning. The relative strengths and weaknesses of a person’s performance on these subtests enable the psychologist to understand how a person processes information.
WAIS-3 provides index scores for Verbal Comprehension, Perceptual Organization, Working Memory and Processing speed. The nonverbal scale also enables the psychologist to measure cognitive potential with relatively limited intrusion from verbal abilities. The Verbal Scale of the WISC III includes the following areas: Information: This measures how much general information a child has learned from home and school. Comprehension: This measures how well your child can think abstractly and understand concepts. Similarities: This also measures a child’s ability to think abstractly.
Children are asked to tell how things are alike or different. Arithmetic: This is not a paper-and-pencil arithmetic task. Rather, it measures mathematical reasoning skills. Vocabulary: Children are required to tell what a word means. A dictionary definition is not necessary; they can explain it. Digit Span: This measures a child’s ability to remember a sequence of numbers (forward and backward). This test is optional; it does not have to be given. The Performance Scale of the WISC III includes the following areas: Picture Completion: Children have to look at pictures and tell the examiner what part is missing.
Picture Arrangement: This requires a child to put pictures in order so that the story makes sense. It measures a child’s ability to provide the whole when only parts are given. Block Design: Unlike Picture Arrangement, where children are given parts and make up the whole, this test measures a child’s ability to look at the whole first, then break it into parts, then reconstruct the whole. It provides blocks and pictures, and the child must put the blocks together to make the picture of the blocks. Object Assembly: The child is given puzzle parts and must complete the puzzle.
It measures a child’s ability to make a whole out of its parts. Coding: This section measures a child’s ability to decipher a code and copy the correct symbols in a specific period of time. Mazes: The child has to find the way out of a maze by using a pencil. Performance is also based on time. When evaluating the results of this test, the psychologist is looking for overall potential to learn. The WISC III will yield three scores: Verbal I. Q. , Performance I. Q. , and Full-Scale I. Q. The average I. Q. score will fall between 90 and 110. But the score is not enough. The Stanford-Binet Intelligence Scale:
The Stanford-Binet intelligence scale is a direct descendent of the Binet-Simon scale, the first intelligence scale created in 1905 by psychologist Alfred Binet and Dr. Theophilus Simon. It provides a mental age that can be converted to an Intelligence Quotient (I. Q. ) score. Although it presents items that require either verbal or nonverbal performance, it tends to have many more verbal items; thus, the Wechsler Scales tend to be used more often. The Stanford-Binet intelligence scale is used as a tool in school placement, in determining the presence of a learning disability or a developmental delay, and in tracking intellectual development.
In addition, it is sometimes included in neuropsychological testing to assess the brain function of individuals with neurological impairments. The Stanford-Binet scale tests intelligence across four areas: verbal reasoning, quantitative reasoning, abstract/visual reasoning, and short-term memory. The areas are covered by 15 subtests, including vocabulary, comprehension, verbal absurdities, pattern analysis, matrices, paper folding and cutting, copying, quantitative, number series, equation building, memory for sentences, memory for digits, memory for objects, and bead memory.
All test subjects take an initial vocabulary test, which along with the subject’s age determines the number and level of subtests to be administered. Total testing time is 45-90 minutes, depending on the subject’s age and the number of subtests given. Raw scores are based on the number of items answered, and are converted into a standard age score corresponding to age group, similar to an IQ measure.